Lipid metabolism in cells in culture will be investigated using vascular smooth muscle cells, human diploid fibroblasts, and selected transformed cells. The uptake and loss of glyceride lipids, fatty acids, and sterols will be studied, as well as the movement of individual lipids and fatty acids within the cells. Polyunsaturated acids and radioactive fatty acids and sterols will be used to follow the metabolic pathways. An important aspect of the project will be to examine the effects and roles of blood proteins and sera on the metabolism of the lipids. The sera will be derived from subhuman primates maintained on different atherogenic and non-atherogenic diets. The individual blood proteins will include albumin and several globulins, as well as their delipidized counterparts. The influence of hormones and mitogens such as platelet growth factor on these various aspects of lipid metabolism will be investigated. All of the studies are related to the overall problems associated with diseases such as atherosclerosis that involve derangements in normal cellular lipid profiles and concentrations. BIBLIOGRAPHIC REFERENCES: Rosenthal, M.D. and R.P. Geyer. Release of phospholipid acyl groups from fetal human fibroblasts. Biochem. Biophys. Res. Comm. 74: 1456-1462, 1977. Chau, I.Y. and R.P. Geyer. The influence of various serum albumin preparations on sterol excretion in tissue culture. cells. Federation Proc. 36: 1115, Abs. #4460, 1977.